CPFD simulation of petcoke and SRF co–firing in a full–scale cement calciner

Computational particle fluid dynamics (CPFD) simulation is carried out to study the effect of petcoke and solid recovered fuel (SRF) co–firing in a full–scale cement calciner. The simulations are conducted using the Multi–Phase Particle–In–Cell (MP–PIC) approach with the Barracuda Virtual Reactor® 17.3.1 solver.

The results from the CPFD simulation are compared with extensive field measurements of gas temperature and composition at several points in different calciner cross–sections. In the simulation, the SRF particles are divided into three components of plastic, biomass, and inert. The plastic particles go through drying, melting and decomposition while the conversion of biomass particles involves drying, devolatilization, and char oxidation.

The predicted concentrations of O2 and CO2 are in good agreement with the measurements, while the gas temperature is overpredicted, especially in the lower calciner vessel. However, the trends of changes in the gas temperature are well–captured. The converted fuel fraction and calcination factor are predicted with an acceptable degree of accuracy.

The simulation results show that large biomass particles in SRF tend to leave the calciner without complete conversion. Furthermore, a recirculation pattern for SRF particles is observed in the lower calciner vessel and the conical section, leading to high conversion degree of this fuel.